U.S. officials have informed several European allies that the delivery of previously contracted American weapons may be delayed, as the ongoing war with Iran continues to put pressure on Washington's stockpiles, citing five sources familiar with the matter.

The delays are expected to affect multiple countries, including in the Baltic region and Scandinavia, the sources said, speaking on condition of anonymity because the discussions were not public, The Caspian Post reports, citing foreign media.

Some of the weapons were purchased through the Foreign Military Sales (FMS) program but have not yet been delivered. U.S. officials recently informed European counterparts in bilateral messages that those shipments will likely be postponed.

The Pentagon did not respond to requests for comment, while the White House and State Department referred inquiries there.

European officials say the situation puts them in a difficult position. Under the FMS program, countries buy U.S.-made weapons with Washington’s approval and logistical support, a system the U.S. has promoted under President Donald Trump to shift more defense responsibility to Europe.

But delivery slowdowns have fueled frustration in European capitals, with some officials increasingly considering European-made alternatives.

U.S. officials argue the weapons are needed for the Middle East conflict and have criticized European allies for not doing more to help reopen the Strait of Hormuz.

Even before the Iran war, U.S. stockpiles had already been drawn down by billions of dollars’ worth of weapons supplied after Russia’s 2022 invasion of Ukraine and Israel’s operations in Gaza.

Since the Iran campaign began, Tehran has launched hundreds of ballistic missiles and drones at Gulf countries. Most have been intercepted, including using PAC-3 Patriot interceptors - the same systems Ukraine relies on for defense.

The delayed shipments include various types of ammunition used for both offensive and defensive purposes, the sources